This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Protein structure prediction is one of the most challenging areas in theoretical biophysics, and it plays an essential role in structural genomics and rational drug design. We have recently developed two novel statistical energy functions: OPUS-Ca, a C-alpha-based potential function composed of seven representative molecular interactions;and OPUS-PSP, an orientation-dependent statistical all-atom potential derived from side-chain packing. We wish to apply these two potential functions to OPUS, a conceptually new structure prediction method that employs multi-scale, multi-layer and top-down prediction strategies. OPUS combines template-based and de novo methods to predict 3D protein structures from primary sequences.